I've found the most accurate bullet in both of my 45-70s is Lyman # 457102, 445 grain GC'd cast bullet with a case full of IMR 4064, very accurate and very powerful. For plinking and play 250 grain SWC, one of Lyman's screw ups, grossly over sized, with 13 grains of Unique with a 2 inch square of Kleenex holding it back against the primer.

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